Wireless digital networks, such as networks operating under the current Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards, are spreading in their popularity and availability. However, resource allocation and management has become increasingly important to achieve energy efficiency, improve network capacity, and provide multi-level function and priority support.
An effective resource allocation management of wireless network resources has many advantages. First, effective resource allocation management can facilitate energy savings. Specifically, with adequate information provided, a control-plane mechanism may determine the least number of network devices in the wireless network to turn on without losing connectivity by any wireless client devices.
Second, effective resource allocation management can also improve utilization of wireless network capacity. Specifically, the control-plane mechanism may facilitate spatial utilization of wireless communication bands, for example, by reducing interference in the horizontal plane and maximizing frequency utilization in the vertical plane.
Third, effective resource allocation management further improves management of multi-functional network devices. Today, many network devices on the markets are capable of serving multiple network functionalities based on configurations. For example, an access point device may be configured to act as a network access provider under some circumstances, and to act as a spectrum monitor under other circumstances. Information provided by the resource allocation and management system can help the control-plane mechanism to determine how to configure functions of the network devices in a wireless network.
In addition, effective resource allocation management can also improve priority management of multiple network devices. It allows multiple network devices of the same or similar type to be organized in a hierarchical manner. Thus, some network devices will be given higher priority in the wireless network than other network devices of the same or similar type, and be placed at a hierarchical level that corresponds to a higher priority.
Various conventional resource allocation methods exist in wireless networks. A typical resource allocation method assigns, for each wireless client device, an access point from set A, a channel (pair) from set C, and a transmitter power such that all wireless links between the access point and the wireless client device meet a predetermined Signal-to-Interference Ratio (SIR) requirements.
Existing channel assignment mechanisms, such as Fixed Channel Allocation (FCA) and Dynamic Channel Allocation (DCA), typically are based on simple heuristic rules. For example, FCA provides for fixed reuse and assignment of wireless communication channels by sectorization and directional antennas. FCA partitions the available spectrum into channel sets. The reuse distance constraint is usually satisfied by assigning the channel sets to the cells in each cluster as determined by, e.g., a graphical coloring scheme. On the other hand, with DCA, channels are temporarily assigned for use in cells for the duration of a wireless call session according to the current system conditions and user needs rather than relying on a priori information. Furthermore, transmitter power control schemes can adjust the transmit powers of all wireless users such that the SIR of each user meets a predetermined minimum threshold required for acceptable performance.
Note that, conventional resource allocation methods have many limitations. For example, conventional resource allocation methods do not provide any ways of computing a minimal coverage set that specifies or identifies the minimum number of radios that is required for coverage on a given wireless frequency band. Due to the importance of resource allocation management, it is desirable for an enhanced resource allocation method that is more effective in improving energy efficiency and network capacity, and in providing multi-level function and priority supports for network devices.